1. Field of the Invention
The present invention relates to a micro-pump, and more particularly, to an electro-hydrodynamic micro-pump having improved characteristics and a method of operating the same.
2. Description of the Related Art
Micro-pumps that pump minute amounts of solution can be used for micro-chemical analysis systems, medical equipments for organ transplantation, micro liquid medicine injectors, and cooling systems for electronic devices.
Example of such micro-pumps include mechanical micro-pump having a rotation pump or a vibration diaphragm, electro-hydrodynamic (EHD) micro-pumps, magneto-hydrodynamic (MHD) micro-pumps, and phase change micro-pumps as a pumping mechanism.
An EHD micro-pump is able to move a polar liquid without a mechanical driving unit. The polar liquid can be a polar solvent such as ethanol, propanol, or acetone. The EHD micro-pump induces flow of a polar liquid by forming an electric field in the polar liquid, and the polar liquid flows along a direction of a traveling electric field.
Contemporary EHD micro-pump, however, requires high electric field to induce a flow of a polar liquid, or requires a bulky structure that is not convenient to flow liquid in a micro-device such as a semiconductor chip.
Present invention provides a novel structure of EHD micro-pump, which requires low electric field to induce a flow of a polar liquid, and can be manufactured in a smaller size.